Osprey

Pandion haliaetus (Linnaeus, 1758)

Description

Male and female of Osprey are similar. Adult Ospreys have dark-brownish upperparts, buffy-white head with broad brownish patch passes from forehead to nape; same dark-brownish strips passes across eyes and ears; all underparts are buffy-white with dark spats on craw; underwings are pale with marble pattern; flight feathers are brownish above; tail is cross-barred. Juveniles in first plumage are dark-brownish above with whitish edges of feathers, especially on shoulders and wing coverts; crown is whitish in brownish shift-streaks (extended feathers of nape formed crest); flight feathers are dark-brownish with pale bases; tail feathers are dark cross-barred.This plumages in second year changed by final plumage of adult bird. Eyes are yellow, bill is bluish on base, black-horn in median and on tip; legs are leaden sometimes greenish tinged; claws are black. SIzes: males wing 448-492, females wing 485-515, males tail 207, females tail 227, tarsus 50-65 mm. Weight: 1300-1900 gr.

Distribution

Osprey breeds on Markakol lake in Southern Altai, on Irtysh, Chernyy Irtysh and Ile valleys, in Balkhash-Alakol depression, in Syrdarya and Ural river valleys. In summer recorded in Naurzum Reserve. Widespread on migration, even in Betpak-Dala and in Ustyurt.

Biology

Osprey is rare breeding migrant. It inhabits fish lakes and rivers with arboreal vegetation. In spring Osprey arrives on water free of ice; in southern areas migration begins in end of March - early April and continues to early May. In northern areas and on Markakol lake Osprey appears in April. Birds migrate singly, though in places up to 5 birds can be seen on 1 km of shore. Pairs are formed in breeding areas. Osprey nests in separate pairs, on 2-15 km one from another, and up to 1 km from the water. Nest is built on trees (Poplar, Ash, Larch), especially on trees with broken top, on 4-20 m above ground; shallow cup-shaped nest is built from twigs, and is lined with dry grass; usually nest is used during several years. Clutches of 2-3, rarely 4 eggs founded from end of April to late May. More than a month both parents incubate and feed juveniles, which begin to fly mainly in mid-August. Autumn migration passes from September to mid-October.